Tag: solar cycle

Sunspot update October 2018: Deepening minimum

9:04 am

The monthly NOAA update of the solar cycle, covering sunspot activity for October 2018, was released yesterday. As I have done every month since this website began in July 2011, I am posting it below, annotated to give it some context.

Though there was a tiny uptick in sunspot activity on the Sun in October, the uptick was inconsequential. Overall, the activity in the past few months appears to closely match the weak activity seen in late 2007 and early 2008, just when the last solar minimum began.

October 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

As I noted in August, the NOAA graph is now getting very close to its right edge, which ends in December 2018. They will very soon have to update this graph so that it can take us into the next solar cycle. While they must do this, it will unfortunately end the standard visual used by them for more than a decade for showing the progress of the solar cycle. Depending on how they change it, I might be able adapt it to include this graph to allow a continuation of the same visual into the future. We will have to see.

Having seen now the full solar maximum for this cycle (weak and short), we are now moving to the next question: Will the developing solar minimum be as long and as deep as the last? Will it evolve into a grand minimum, lasting decades, as some solar scientists believe?

Or will the Sun return to the higher levels of activity seen during most of the 24 solar cycles observed since the last grand minimum in the 1600s?

Since our understanding of these changes is very poor, your guess is likely as good as anyone else’s. All we can really do is keep our eyes open and watch what happens.

One comment

Sunspot update September 2018: Minimum!

9:58 am

NOAA yesterday released its monthly update of the solar cycle, covering sunspot activity for September 2018. As I have done every month since this website began in July 2011, I am posting it below, annotated to give it some context.

Sunspot activity on the Sun in September dropped slightly from August. More significantly, the activity continues to match closely the weak activity seen in 2008, when the Sun last went through its last solar minimum. We are unquestionably now in the new minimum, and its arrival in the past few months makes the now-ending solar cycle about one to two years shorter than predicted.

September 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

As I noted last month, the NOAA graph is now getting very close to its right edge, which ends in December 2019. They will very soon have to update this graph so that it can take us into the next solar cycle.

What that new cycle will bring will be the next mystery. I have been following this cycle now since its unusual beginning, with a solar minimum much much longer and more inactive than any solar scientist had ever expected. We can only guess at the surprises the Sun will give us in the coming decade, especially since the science of solar sunspot activity remains superficial and in its infancy. We do not really understand why the Sun’s activity fluctuates. Nor do we understand why it periodically stops producing sunspots for long periods, resulting in what solar scientists call a grand minimum.

There are some scientists who think another grand minimum is coming. We shall have to wait and see. I certainly am going to follow their upcoming observations, as this work remains one of the great scientific studies humans are presently pursuing.

5 comments

Sunspot update for August 2018: The slide to minimum

12:28 pm

As it does the first Sunday of each month, yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for August 2018. And as I do every month, I am posting it below, annotated to give it some context.

The Sun in August had a slight uptick in sunspot activity, but not a very significant one. As such, the slide to solar minimum continues. Right now the lack of sunspot activity in 2018 is heading to match or even exceed 2007, the year in which the previous solar minimum began.

August 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

If you look at the original graph at NOAA, you will see that we are getting very close to the right edge of the graph. I expect that sometime in the next few months NOAA will update the graph, a necessary act that will in one sense be a shame, as they have been adding monthly updates to this graph since the beginning of the last solar minimum. This has allowed everyone to see a standard visual, month to month, for comparing solar activity. It has also allowed me to annotate the graph properly to show how the 2007 and 2009 predictions held up against actual activity. Once the graph changes it will be more difficult to do this.

Anyway, it is very clear we are entering solar minimum, and that the solar cycle we are now completing will be both a short and weak cycle. What happens next is really the big question. Will the Sun sunspot activity recover? Or will we enter the first grand minimum since the 1600s? Either way, for solar scientists the coming years are going to be very exciting.

Posted on interstate 10 going from Tucson to Phoenix, on the way to the wooded northern forests of Arizona, where Diane and I will spend a couple of days visiting friends at their upstate cabin/home.

10 comments

Sunspot update for July 2018: The Sun flatlines!

10:50 am

Yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for July 2018. As I do every month, I am posting it below, annotated to give it some context.

This might be the most significant month of solar activity that has been observed since Galileo. Except for two very short-lived and very weak sunspots that observers hardly noted, the Sun was blank for entire month of July. This has not happened since 2009, during the height of the last solar minimum.

What makes this so significant and unique is that it almost certainly signals the return of the next solar minimum, a return that comes more than a year early. The solar cycle the Sun is now completing has only been ten years long. It is also one of the weakest in more than a hundred years. This combination is unprecedented. In the past such a weak cycle required a long cycle, not a short one.
» Read more

9 comments

Sunspot update for June 2018: Activity increases again

5:56 pm

NOAA today posted its monthly update of the solar cycle, covering sunspot activity for June 2018. Below is this month’s annotated graph.

For the third straight month the Sun showed a small increase in sunspot activity. The pattern also continued to follow the two-week-on/two-week-off pattern of activity caused by the Sun’s 27-day rotation, as I described in my update last month.

June 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction. The yellow line compares the present activity with the activity during solar minimum in 2008 and 2009.

This pattern is continuing. As of today, there have been no sunspots since June 28, almost two weeks. I would not be surprised if some sunspots appeared within the next week, especially because today’s image of the Sun from Solar Dynamic Observatory shows bright faculae rotating into view. Faculae are, like sunspots, a sign of solar magnetic activity. The two usually go together.

2 comments

Sunspot update for April 2018: Heading into solar minimum

9:00 am

On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for April 2018. Below is my annotated version of that graph.

While there was an uptick in sunspots in April, compared to the almost complete inactivity in March (the least active month for sunspots in a decade), the uptick did little to change the general trend. Sunspot activity is now comparable to what we saw in early 2008 (as indicated by the yellow line). This was just before the arrival of the previous solar minimum, which happened to also be one of the longest and deepest on record.

» Read more

One comment

The first sunspots of the next solar cycle

9:53 am

In linking to my sunspot update this week, there has been a lot of speculation at the climate website WattsUpWithThat that the next solar cycle has begun.

Our resident solar physicist, Dr. Leif Svalgaard commented and provided a link to something reported by his colleagues, something that likely would not have been possible without the fantastic solar observations of NASA’s Solar Dynamic Observeratory (SDO). He said: “Cycle 25 has already begun. It looks to me that SC25 will be a bit stronger than SC24, so probably no Grand Minimum this time.” It seems a small sunspot has been observed, that has the opposite polarity of cycle 24 sunspots. [emphasis in original]

The speculation at WattsUpWithThat, which suggested that this sunspot was the first such sunspot this cycle, was not quite accurate however. This sunspot with an opposite polarity, which decayed so quickly that it did not rate getting a sunspot number, was not the first. This week the Solar-Terrestrial Centre of Excellence, a Belgian organization focused on space-solar science, published this very good article discussing not only this sunspot but two others, one of which occurred more than a year ago.
» Read more

4 comments

Sunspot update for March 2018: the sun crashes!

11:49 am

It surely looks like the solar minimum has arrived, and it has done so far earlier than expected! On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for March 2018. Below is my annotated version of that graph.

March 2018 was the least active month for sunspots since the middle of 2009, almost nine years ago. In fact, activity in the past few months has been so low it matches the low activity seen in late 2007 and early 2008, ten years ago when the last solar minimum began and indicated by the yellow line that I have added to the graph below. If the solar minimum has actually arrived now, this would make this cycle only ten years long, one of the shortest solar cycles on record. More important, it is a weak cycle. In the past, all short cycles were active cycles. This is the first time we have seen a short and weak cycle since scientists began tracking the solar cycle in the 1700s, following the last grand minimum in the 1600s when there were almost no sunspots.
» Read more

27 comments

Sunspot update for February 2018

12:25 pm

It’s time for my monthly sunspot update. On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for February 2018. Below the fold is my annotated version of that graph.

Sunspot activity in February continued the low activity seen in November, December, and January, with November 2017 still the most inactive month for sunspots since the middle of 2009. In fact, the low activity we are seeing now is somewhat comparable to the low activity seen during the ramp down to solar minimum in the first half of 2008. By the end of that year we had hit solar minimum, the deepest and longest in a hundred years, suggesting that we might even hit solar minimum before the end of this year. That would have this happen at least a year earlier than all predictions.
» Read more

One comment

Sunspot update for January 2018

11:51 pm

Today NOAA posted its monthly update of the solar cycle, covering sunspot activity for January 2018. Below is my annotated version of that graph.

As you can see, the low sunspot activity of the past two months continued in January. November 2017 remains the most inactive month for sunspots since the middle of 2009. January is now the second most inactive month, with December a very close third.

January 2018 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Though activity continues to track close to but considerably below the 2007 weak prediction, the difference appears to be increasing as the ramp down to solar minimum continues. While I have said in past updates that the trend suggests an early arrival of the solar minimum, a close look at the previous ramp down in 2007 and 2008 shows that when activity became this weak, the ramp down slowed considerably. This previous pattern suggests that we could see another year or two of similarly low activity before the minimum arrives.

Regardless, the low activity, this soon, continues to suggest that the next maximum will also be weak, and might even not come at all, as some solar scientists have proposed. Instead, we might be heading toward another Grand Minimum, with no significant sunspots for decades.

Will that Grand Minimum produce cold weather worldwide, as it appears to have done during the last Grand Minimum in the 1600s? There is circumstantial evidence in the past decade that it might. We will not know, however, until it happens, and that possibility remains very uncertain.

4 comments

Sunspot update for December 2017

2:40 pm

The precipitous decline in sunspots continues. While November 2017 remains the most inactive month for sunspots since the middle of 2009, December was a very close second.

Below is my annotated version of NOAA’s monthly update of the solar cycle, covering sunspot activity for December, which they posted on Sunday.

December 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

December 2017 sunspot record

The graph on the right, produced by SILSO (Sunspot Index and Long-term Solar Observations) on December 31, shows only 14 days during the month when there were sunspots active on the Sun’s visible hemisphere. This is only four more days then seen in November. And like November, the few sunspots were weak, resulting in tiny sunspot numbers total.

The first graph above illustrates how weak this on-going sunspot cycle has been. While the curve most closely matches the 2007 weak prediction of half the solar science community, it has one very notable difference. The actual ramp up to solar maximum started two years later than predicted, even though it appears to be ending when that prediction expected. The result is a very very short solar cycle, something that has historically always been associated with very active and intense sunspot activity. Instead, this short cycle has only seen weak activity, generally below all the predictions.

All signs continue to point to an early arrival of solar minimum. They also suggest that the next maximum will also be weak, and might even not come at all, as some solar scientists have proposed. Instead, we might be heading toward another Grand Minimum, with no significant sunspots for decades.

So, is it cold outside right now? Well, that’s weather, not climate. Nonetheless, there is a lot of circumstantial evidence that few sunspots correspond with a cooling climate on Earth. (The last grand minimum occurred in the 1600s, during what was called the Little Ice Age.) There is even some preliminary evidence to suggest that cosmic rays might be a cause. (Watch the video at the end of this link.).

Whether any of this will happen however remains unknown. We will need to wait to find out.

Leave a comment

The Sun goes quiet! Sunspot update for November 2017

11:51 am

The past month was the most inactive month for sunspots since the middle of 2009, when the last solar minimum was just ending and the Sun was beginning its ramp up to solar maximum.

NOAA on Sunday posted its monthly update of the solar cycle, covering sunspot activity for November. As I have done every month since 2010, I have posted that graph below, with annotations.

November 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

I have also added a straight yellow line near the bottom of the graph, indicating how the lack of activity this past month corresponds with the lack of activity in the summer of 2009, just when that unusually long and deep solar minimum was beginning to end.

November 2017 sunspot record

To get an idea how few sunspots were seen in November, the graph on the right, produced by SILSO (Sunspot Index and Long-term Solar Observations) on December 1, shows only 10 days during the entire month when any sunspots were active on the Sun’s visible hemisphere. And even those sunspot were few and weak, resulting in tiny sunspot numbers total.

Nor is December looking any different, with no sunspots recorded so far, four days into the month.

The plunge to solar minimum continues to appear to be happening faster than normal. At this pace, solar minimum will arrive in early 2018, making this one of the shortest solar cycles on record. That in itself would be unprecedented, as short cycles in the past have always accompanied very active solar maximums, not weak maximums like the maximum we have just seen.

I still expect the ramp down to solar minimum to slow down and stretch out to 2019, as would be more normal, but I also would not bet any money on this expectation, at this point.

The big question remains: Will the solar cycle continue as normal after this upcoming solar minimum, or will we instead see our first grand minimum since the Maunder Minimum in the 1600s, a period lasting for about a century with no obvious sunspots that also corresponded to the Little Ice Age?

7 comments

Sunspot update for October 2017

9:23 am

NOAA today posted its monthly update of the solar cycle, covering sunspot activity for October. That graph is posted below, with annotations.

October 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

After two straight months of rising sunspot activity, the number of sunspots plunged in October, returning the numbers almost exactly back to the general trend we have seen since 2014 when the solar maximum ended. While the short two month increase indicated that the minimum will not occur as soon as this long term trend suggests, the quick return to that trend this month suggests that it will.

Meanwhile, November is six days old and has yet to see any sunspots at all.

6 comments

Sunspot update for September 2017

9:38 am

On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for September. That graph is posted below, with annotations.

September 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Last month saw the strongest amount of sunspot activity in a year, thus helping to bring the pace in the decline of sunspot activity back towards the low prediction from April 2007. This also suggests that the ramp down to solar minimum will continue through 2019, with minimum not occurring before then, at the earliest. At the same time, the increase in sunspot activity seen in September seems to have eased in October, with the return of a blank Sun this past week.

2 comments

Sunspot update for August 2017

10:52 am

Yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for August. That graph is posted below, with annotations.

August 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The long slow decline to solar minimum has now shown itself. Up until now, the ramp down from solar maximum had been fast and steep, unlike past solar cycles where the ramp down is slow and steady. The last few months the ramp down had practically ceased. In this August graph the ramp down turned into a temporary ramp up. Considering the strong activity going on right now as well as the past week, I expect the September numbers to also show this increase.

None of this means that the ramp down has ended, or that we will not see a solar minimum. All it means is that it takes awhile for the Sun to slowly calm down after each solar maximum. The sunspots we are seeing right now, all near the equator, are from the solar cycle now slowly ending. We will know the minimum is coming as well as the next solar maximum when the first tiny and rare sunspots appear in high latitudes. These high latitude sunspots will belong to the next cycle, and will have reversed polarity.

2 comments

Sunspot update for July 2017

10:06 am

NOAA today posted its monthly update of the solar cycle, covering sunspot activity for July. As I have done every month since 2010, the graph is posted below, with annotations.

July 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Sunspot activity in July remained almost exactly the same as in both May and June. This is the first indication that this cycle’s ramp down from solar maximum will follow the standard pattern of a slow and extended decline to minimum. Up until now the drop in sunspot activity has been as fast as the increase during ramp up. Historically the ramp down has instead been slower, sloping downward gently and over a much longer time period. The last few months suggest that this cycle’s end is beginning to resemble past cycles.

Meanwhile, a review of past solar cycles by German scientists suggests that a cyclical cooling period in the Sun’s output is coming, and that such ups and downs can be tracked in the solar record.

In order to elucidate the solar influence, we have used a large number of temperature proxies worldwide to construct a global temperature mean G7 over the last 2000 years. The Fourier spectrum of G7 shows the strongest components as ~1000-, ~460-, and ~190 – year periods whereas other cycles of the individual proxies are considerably weaker. The G7 temperature extrema coincide with the Roman, medieval, and present optima as well as the well-known minimum of AD 1450 during the Little Ice Age. We note that the temperature increase of the late 19th and 20th century is represented by the harmonic temperature representation, and thus is of pure multiperiodic nature. It can be expected that the periodicity of G7, lasting 2000 years so far, will persist also for the foreseeable future. It predicts a temperature drop from present to AD 2050, a slight rise from 2050 to 2130, and a further drop from AD 2130 to 2200. [emphasis mine]

Note that this prediction is not based on any real understanding of the Sun’s sunspot cycle or what causes any variations in its brightness. All they have done is extrapolate into the future the patterns of past fluctuations. This is as if a weatherman averaged how many times it normally rains in your town, and then predicted rain in the next few days merely by those averages. “It rains on average every three days, so because it rained yesterday expect no rain for the next two days!”

Nonetheless, the past fluctuations seem to follow a cyclical pattern, and thus also appear to confirm other studies that suggest we are heading towards another grand minimum, with no sunspots for decades, which also in the past corresponded with cooler global temperatures.

One comment

Sun’s core rotates 4X faster than surface

8:24 am

The uncertainties of science: Scientists have discovered that the core of the Sun rotates four times faster than its surface layers.

The rotation of the solar core may give a clue to how the sun formed. After the sun formed, the solar wind likely slowed the rotation of the outer part of the sun, he said. The rotation might also impact sunspots, which also rotate, Ulrich said. Sunspots can be enormous; a single sunspot can even be larger than the Earth.

The researchers studied surface acoustic waves in the sun’s atmosphere, some of which penetrate to the sun’s core, where they interact with gravity waves that have a sloshing motion similar to how water would move in a half-filled tanker truck driving on a curvy mountain road. From those observations, they detected the sloshing motions of the solar core. By carefully measuring the acoustic waves, the researchers precisely determined the time it takes an acoustic wave to travel from the surface to the center of the sun and back again. That travel time turns out to be influenced a slight amount by the sloshing motion of the gravity waves, Ulrich said.

This phenomenon had been predicted more than twenty years ago, but never observed until now.

4 comments

New data suggests Sun undergoing fundamental changes

8:40 am

The uncertainty of science: New data, when compared with similar data collected over decades, suggests the Sun’s solar cycle is undergoing some fundamental changes.

In work just published in the Monthly Notices of the Royal Astronomical Society, the team shows that the interior of the Sun has changed in recent years, and that these changes persist in the current cycle. In combination with theoretical models, the observations suggest that the magnetic field distribution in the outer layers may have become a bit thinner. Other seismic data shows that the rotation rate of the Sun has also undergone some changes in the way the Sun rotates at different latitudes.

“Again, this is not how it used to be and the rotation rate has slowed a bit at latitudes around about 60 degrees. We are not quite sure what the consequences of this will be but it’s clear that we are in unusual times. However, we are beginning to detect some features belonging to the next cycle and we can suggest that the next minimum will be in about two years,” says Elsworth.

First, they don’t know what will happen because of these changes. Second, their data confirms that the solar minimum will occur in about two years, which would make this cycle only 9 years long, one of the shortest but also one of the weakest that has been observed, two things that previously had never gone together.

3 comments

Sunspot update for June 2017

11:47 am

Today NOAA posted its monthly update of the solar cycle, covering sunspot activity for June. As I have done every month since 2010, the graph is posted below, with annotations.

June 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Sunspot activity in June was almost exactly the same as in May, and thus continued the overall downward trend that is below the 2007 low prediction and that suggests that this very weak solar maximum will end much earlier than predicted, and will make it an unprecedented short but weak cycle. The Sun is once again blank today for the first time in about two weeks, repeating the pattern we have seen for several months where, because one hemisphere of the Sun is blank while the other hemisphere has some sunspots, the rise and fall of the sunspot counts tracks the 27-day solar rotation almost precisely.

There continues to be evidence that the Sun is undergoing significant changes this solar cycle, all of which are pointing to the possibility that a grand minimum is coming, with no sunspots for decades. And as I have said now monthly for six years, past grand minimums have consistently occurred at the same time the Earth’s climate has cooled. The scientific link remains unclear, but if we should undergo a grand minimum in the coming decades, we will finally have the opportunity to find out what that link is.

7 comments

Sunspot update for May 2017

10:32 am

Last week NOAA posted its monthly update of the solar cycle, covering sunspot activity for May. Unfortunately, there appeared to be a problem with their posting software. Though the date of the image changed, the graph itself was not updated. I contacted NOAA, and Ann Newman, IT Specialist at NOAA’s
Space Weather Prediction Center, took a look and quickly fixed the problem.

The corrected graph is posted below, with annotations, as I have done now every month since 2010.

May 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The decline in sunspot activity resumed in May, putting the trend back below the 2007 low prediction. Overall, the trend continues to suggest that this very weak solar maximum will end much earlier than predicted, and will make it an unprecedented short but weak cycle. As the Sun is at this moment blank, and has been for several days, I expect that June will end up with low numbers as well, continuing this trend.

As I have repeatedly said now monthly for six years, if history is any guide, the Sun’s low activity should correspond with cooler temperatures here on Earth. Why this happens is not yet understood, though there are theories.

3 comments

Sunspot update for April 2017

3:53 pm

Today NOAA posted its monthly update of the solar cycle, covering sunspot activity for April. It is posted below, with annotations, as I have done now every month since 2010.

April 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

April showed an uptick in sunspot activity, enough to move the numbers back up above the 2007 low prediction. Nonetheless, activity as the cycle has been ramping down has consistently and generally remained below expectation, and does seem heading to an early arrival of solar minimum, sometime in late 2019 or early 2020, about a year early.

I don’t want to sound like a broken record, as I have written this practically every month since I started these updates in 2010, but this short and weak solar maximum suggests the possibility that we might be facing a grand minimum, where there are no significant sunspots for decades. Some solar scientists think this is coming. Others are much more doubtful. Regardless, we can only wait and watch, while also recognizing that weak solar maximums and grand minimums have in the past consistently coincided with global cool weather. The reasons why this has happened are not yet known, but it has happened nonetheless.

One comment

Sunspot update for March 2017

11:32 am

On April 3, while I was in the Grand Canyon, NOAA posted its monthly update of the solar cycle, covering sunspot activity for March. As I have been doing every month since 2010, I am posting it here with annotations to give it context.

March 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The decline in sunspots continues to run below predictions, suggesting an end to this solar cycle and a solar minimum as early as sometime in 2018. And as I noted in my February update, sunspot activity continues to track the Sun’s 27 day rotation, alternating every two weeks between blank and active hemispheres. We had the longest stretch, more than two weeks, without sunspots in March. This was followed by about two weeks of activity, followed by several blank days and a relatively inactive Sun at present, beginning a little less than a week ago. I expect this period of inactivity to last another ten days or so, and then things will pick up again.

2 comments

The longest stretch of no sunspots since 2009

10:45 am

The Sun just completed its longest stretch, 15 days, without sunspots since 2009, suggesting once again that the solar minimum is coming much sooner than expected.

So far this year the Sun has been blank 34% of the time, a pace that makes this year almost as blank as 2009, the year in which the previous solar minimum ended. This suggests that 2017 might be the year in which the next solar minimum begins, which would be about two years earlier than the earliest predictions.

The more likely scenario is that 2018 will be the year the solar minimum begins, with 2019 when solar activity bottoms out. This will still be much earlier than expected, making this solar cycle only about 9-10 years long. What makes this more significant is that historically short cycles always went with high activity, while long cycles signaled an inactive and weak maximum. This cycle will be the first that is both short and weak.

What happens next remains the big question. Will the Sun enter a grand minimum, with no sunspots for decades? Or will sunspot activity continue? Since solar scientists really do not yet understand the mechanism within the sun’s magnetic field that causes this solar cycle, we really can’t answer these questions, in advance. We must wait, and see.

3 comments

Sunspot update for February 2017

10:04 am

On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for February. As I have been doing every month since 2010, I am posting it here with annotations to give it context.

February 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The decline in sunspots continues. Though the increase in activity from January held in February, the overall activity remains significantly below the predictions, and continues to point to a much earlier arrival of the solar minimum, sometime in 2019.

Leave a comment

The Sun turns

11:33 am

NOAA today posted its monthly update of the solar cycle, covering sunspot activity for January. As I do every month, I am posting it here with annotations to give it context.

January 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Since my last solar cycle update, sunspot activity showed a slight increase in activity when compared to the previous month. Overall, however, the ramp down from solar maximum continues to underperform the predictions, and suggests that this solar maximum will not only be a very weak one, but a short one as well.

January’s activity however illustrated a statistical phenomenon that is typical of the sunspot count. That count is determined not by the numbers of sunspots on the entire surface of the Sun, but on the sunspots visible on the side of the Sun facing the Earth. Since it is not unusual for one face to be more active than the other, as we transition from maximum to minimum the sunspot counts will often show a more pronounced up-and-down curve reflecting this fact. Since the Sun’s day equals about 27 Earth days, this means that about every two weeks the active side will dominate our view until it rotates away and the inactive side reveals itself for two weeks.

Silso daily sunspot graph, January to February 2017

This pattern was very evident in January, as shown by the graph on the right and obtained from here. During the first two weeks of the month the Sun was blank. Then that inactive face rotated out of view. For the next two weeks or so the sunspot count went up, then began to drop as the active face began to rotate out of view to be replaced by the blank face last seen in early January.

This pattern of course is very fluid, as at any time the inactive face can become more active and the active face less so. Nonetheless, for short periods covering one to three months it helps to partly explain the up-and-down pattern of sunspot fluctuations during this time period when large portions of the Sun’s face are blank.

7 comments

The sunspot crash continues

3:49 pm

On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for December. As I do every month, I am posting it here with annotations to give it context.

December 2016 Solar Cycle graph

January 2017 sunspots as of January 9, 2017

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Sunspot activity continues to decline, and it appears to be declining at a steadily faster rate as the solar cycle ramps down towards minimum. Not only did sunspot activity drop below the 2007 low prediction in 2016, since 2017 began the sun has been blank almost continuously, as shown by the graph on the right. The signs continue to point to a solar minimum occurring much sooner than predicted, producing an unprecedented short and weak solar cycle.

Despite this, the appearance in December of the first sunspot for the next solar cycle suggests that we will not be entering a Grand Minimum in the coming decades. It does not guarantee it, as there is some evidence that even though no sunspots were visible during the Maunder Minimum in the 1600s the magnetic activity that causes sunspots did continue, and with our better observation equipment today we may see sunspots they would not have seen in the 1600s.

2 comments

First sunspot for the next solar cycle spotted

11:42 am

Solar scientists have spotted the first sunspot on the Sun with a reversed polarity, meaning that it really belongs to the next sunspot cycle.

This is not unusual. The sunspots from different cycles routinely overlap by several years, with the sunspots from the old cycle moving close to the equator with time and the new cycle sunspots appearing at high latitudes. What this does suggest is that there will be sunspots after the upcoming solar minimum, rather than the beginning of a new Grand Minimum with no sunspots for decades.

Leave a comment

Sunspot activity continues to drop

3:21 pm

NOAA yesterday posted its monthly update of the solar cycle, covering sunspot activity for November. Below is my monthly annotated version of that update.

November 2016 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

In November sunspot activity dropped again, to the second lowest point seen since 2010. Essentially, activity today is about where it was in 2010 when the solar minimum was finally ending. Now, the solar maximum is ending and we are beginning the next solar minimum.

Throughout the entire just completed solar maximum, the Sun continuously under-performed all predictions. Even now, despite following almost precisely the prediction of the 2007 low prediction during 2014 and 2015, in 2016 the ramp down has begun to slip below that prediction. The trend continues to suggest the arrival of solar minimum will be early, possibly as early as sometime late next year.

2 comments

Decline in sunspots continues

10:26 pm

Late Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for October. As I do every month, I am posting it here with annotations to give it context.

October 2016 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The sunspot decline continued in October, dropping the sunspot number for the month to below the 2007 low prediction. Though the decline continues to track that low prediction, the sunspot count for November has been even lower, suggesting that the ramp down to solar minimum will continue to under perform that prediction and will arrive at minimum sooner than expected. As I noted last month, this fast decline will also mean that the ending solar cycle will be a both a weak and a short cycle, two phenomenon that in the past never went together. In the past, a short cycle meant the maximum was strong, while a long cycle would correspond with a weak maximum.

The Sun continues to behave in a manner that is unprecedented, and suggests the possibility that a Grand Minimum might be coming.

One comment
1 2 3 4 5 6 … 9